function Parent4() {
    this.name = 'parent4';
    this.play = [1, 2, 3];
}
function Child4() {
    Parent4.call(this);
    this.type = 'child4';
}
Child4.prototype = Parent4.prototype;
Child4.prototype.constructor = Child4;
var s3 = new Child4();
var s4 = new Child4();
console.log(s3)